This invention relates to center pivot sprinkler irrigation equipment and more particularly to articulating pipe coupling and alignment assemblies interconnecting segments of the water distribution conduit.
Center pivot sprinkler irrigation systems generally involve an elevated water distribution pipe that is rotated about a center point. The distribution pipe is propelled by longitudinally spaced mobile towers. Usually one of the towers, preferably the outermost tower, is adapted to be constantly driven at a pre-determined speed with the intermediate towers being controlled to maintain general alignment between the outer tower and the pivot. Normally the intermediate towers will lag a little behind or proceed ahead of the desired position of alignment causing bending movements to occur in the distribution pipe. Consequently it is desirable to provide pivotal coupling connections between pipe sections to accommodate any angular bending of the distribution pipe both in the horizontal direction and vertical direction. The bending movements are mostly in the horizontal plane about the axis of the distribution conduit, although the pipe may also be subjected to vertical bending moments due to travel of the towers over hilly terraine. Additionally, it is not unusual for substantial tensional and compressional forces to be transmitted along the distribution pipe with transmitting torsional forces. Consequently, it is very important that the coupling between the distribution pipe sections be sufficiently strong to accommodate the various forces while enabling the pipe sections to articulate both in the vertical direction and horizontal direction with respect to each other.
One of the principal objects of the invention is to provide a new articulating coupling and alignment control assembly for interconnecting water distribution pipe sections and is relatively easy to construct and capable of performing the various needed functions.
An additional object of this invention is to provide an assembly that can be readily manufactured with as many common parts as possible to substantially reduce the cost of manufacture and the cost of inventory for replacement parts.
A further object of this invention is to provide an assembly that can be economically manufactured and readily assembled in the field by inexperienced personnel.
A still further object of this invention is to provide an assembly in which an external connection is provided so as not to inhibit the flow of water through the coupling while at the same time maintaining accurate alignment control throughout the length of the distribution conduit.
These and other objects and advantages of this invention will become apparent upon reading the following detailed description of a preferred embodiment.